CHAPTER X - Hilton's Law
In the years l860-61-62 a series of lectures was delivered
by John Hilton, F. R. S., F. R. C. S., "On the Influence of Mechanical and Physiological
Rest in the Treatment of Accidents and Surgical Diseases, and the Diagnostic
Value of Pain." These lectures were afterward published in book form under the
title of "Rest and 'Pain." This book is a medical classic and worthy of careful
perusal by all students of medicine.
The careful observations and reasonings therefrom
which are reported in "Rest and Pain" explain many of the phenomena noted
in osteopathic practice. We desire to give all due honor to this
man who was so far in advance of his time.
We will quote a few paragraphs from "Rest and Pain"
which have a direct bearing on osteopathic methods of diagnosis and therapeutics.
The Law Stated. - After careful study of the
distribution of nerves throughout the body, Hilton sums up his observations
in a terse sentence which we choose to call a law - "The same trunks of
nerves whose branches supply the groups of muscles moving a joint, furnish
also a distribution of nerves to the skin over the insertion of the same
muscles, and the interior of the joint receives its nerves from the same
Hilton further states that "Every fascia of the body
has a muscle attached to it, and that every fascia throughout the body
must be considered as a muscle."
Methods of Studying Anatomy. - These statements
lead us to a closer study of each joint and its controlling muscles and
governing nerve or nerves. We may study anatomy under artificial
divisions such as Osteology, Syndesmology, Myology, etc., and still, after
securing an accurate technical knowledge of details, we have nothing of
practical value. It is in the correlation of these tissues with their
interdependence quite fully understood that we have a working knowledge.
With this thought of the influence of one tissue on another and the harmonious
action secured by the comparatively varied distribution of the nerve trunks,
we find a new and vital interest in anatomy.
This law is based upon the facts of anatomy and physiology,
and makes our concrete knowledge of these subjects of constant practical
value in both diagnosis and therapeutic. This law shows us the "why" of
certain vital and mechanical manifestations, and teaches us practical methods
Example of Hilton's Law. - An example of Hilton's
law is the distribution of the sciatic nerve to the ankle. The muscles
moving the joint, the synovial membrane and most of the skin over the joint
are all innervated by it.
The Knee. - The knee has three nerves.
Each one has a motor and sensory control. The extensor muscles and
the skin over them is innervated by the anterior crural. The flexor
muscles and the skin over them is innervated by the sciatic. The
obturator, in addition to these nerves, furnishes sensory filaments to
the synovial membrane. All the joints of the body may be examined
in the light of this law. The same segment of the central nervous
system which gives off a purely motor nerve trunk, gives off also a sensory
nerve whose filaments are distributed over the same area. Thus it
is sometimes necessary to go to the central nervous system to discover
this association of motor and sensory distribution. In practice we
always do this, because it is easier to work from the center of the areas
The Object of Such a Distribution. - Hilton
says: "The object of such a distribution of nerves to the muscular and
articular structures of the joints, in accurate association, is to insure
mechanical and physiological consent between the external muscular, or
moving force, and the vital endurance of the parts moved, namely, of the
joints, thus securing in health a true balance of force and friction until
"Without this nervous association in the muscular
and articular structures, there could be no intimation by the internal
parts of their exhausted condition." "Again, through the medium of the
muscular and cutaneous nervous association great security is given to the
joint itself by those muscles being made aware of the point of contact
of any extraneous force or violence. Their involuntary contraction
instinctively makes the surrounding structures tense and rigid, and thus
brings about an improved defence for the subjacent structures."
The Uniformity of the Law. - "This articular,
muscular and cutaneous distribution of the nerves is, in my opinion, a
uniform arrangement in every joint in the body. We may find numerous
illustrations of the same method of distribution in other parts of the
body, which have the same definite relations to each other, and in this
respect present the same physiological and mechanical arrangement observable
in joints. This same principle of arrangement, anatomically, physiologically
and pathologically considered, is to be observed with an equal degree of
accuracy in the serous and in the mucous membrane. Thus considered, it
presents a principle which, if it has any application in practice, must
be one certainly of large extent."
Precision of Nervous Distribution to Muscles.
- "The great precision with which muscles are supplied by their nerves
is worthy of remark; and is such that if we have before us a contracted
muscle, we may be sure of the nerve which must be the medium, or the direct
cause of it."
"In studying the supply of nerves to muscles over
every part of the body, we find a great degree of precision, which marks
one difference between their distribution and that of the arteries."
Indications for Use of Therapeutics. - I should
say in aid of other means, employ this cutaneous distribution of nerves
as a road or means toward relieving pain and irritation in the joint.
You thus quiet the muscles, prevent extreme friction, and reduce muscular
pressure and spasm. Therapeutics may certainly reach the interior
of this joint and its muscles through the medium of the nerves upon the
surface of the skin, and so induce physiological rest to all the parts
concerned in moving the joint.
The advantage to be derived arises in this way: Sensibility
of the filaments supplying the skin being reduced, that influence is propagated
through the sensitive nerves to the interior of the joint and to the muscles
moving a joint. This diminution of sensibility tends to give quietude
or perfect rest to the interior of the joint, which is one of the most
important elements towards the successful issue of the treatment of cases
of this kind."
The Use of Hilton's Law in Physical Diagnosis.
- Hilton's law is applicable in physical diagnosis. The osteopath
makes constant use of the superficial expressions of nerve activity.
After having learned the whole course, distribution and central connections
of the nerve, we can judge rightly as to the structures involved by noting
the physiological conditions of all the structures innervated by a definite
nerve trunk. Hilton applied his law entirely from the physiological
side, i. e., he observed changes in the relations of joint structures,
but considered the deformity as due to excessive physiological action of
the muscles in their effort to secure rest for the joint surfaces.
This is largely true, but he did not question how the process was initiated.
The osteopath seeks a point of stimulus to the nerves controlling a joint
or other structure, believing that it is of little value to anaesthetize
nerve endings and give. rest so long as this stimulus is allowed to arouse
impulses in the nerve fibers.
Comparison of Methods. - To compare methods
of using Hilton's Law, we will note one of his cases, and a similar one
treated osteopathically. In Chapter VIII of "Rest and Pain" he describes
a case of inflammation of the shoulder joint, and mentions that the joint
is fixed in a position of rest as a result of the association of nerves
to the synovial membrane, the muscles of the joint and the skin over the
joint. Anaesthesia releases the fixedness of the joint, because the
muscles do not contract after the sensory impulses are deadened by the
anaesthetic. He says, "Therapeutics may certainly reach the interior
of this joint and its muscles through the medium of the nerves upon the
surface of the skin, and so induce physiological rest to all parts concerned
in moving the joint. I mean to say that these nerves upon the surface
of the skin being in direct association with the interior of the joint
itself, we may reduce the muscular spasm as well as the sensibility of
the interior portion of the joint, by applying our anaesthetics with accuracy
and with sufficient intensity upon the exterior of the deltoid muscle,
over the distribution of these sensitive filaments. The thought will
occur to you at once that there is nothing very remarkable in this opinion,
and that is quite true. The embrocations, however, which would ordinarily
be suggested for this purpose, are not of a character sufficiently potent
to alleviate the pain of the patient, and are, I believe, seldom employed
with a definite idea in the mind of the prescriber. I would suggest
that we should employ our fomentations strongly. medicated with belladonna,
with opium or with hemlock, instead of using mere fomentation of hot water.
Some will say, 'Oh, hot water is quite as good;' but I can assure you practically
that it is not so."
You will note that he makes use of the cutaneous
reflexes to affect the interior of the joint.
A recent case, corresponding we believe, was treated
osteopathically with marked success. The inflammation in the shoulder
joint was not traumatic in origin nor did it appear to be rheumatic in
character. Hot fomentations would give great relief, but did not
give sufficient rest to the joint to permit of a cure. The fear was
entertained that longer rest of the articulation would result in adhesion
and loss of function in the joint. Since the circumflex nerve appeared
to be the one involved, a careful examination was made of the articulation
. s between the sixth and seventh cervical vertebrae. The circumflex
nerve is made up largely of fibers from the sixth cervical nerve trunk.
Tension and tenderness, together with slight rotation of the sixth cervical
were noted at this point. The osteopath, instead of working over
the area of distribution of the circumflex, centered his work upon this
articulation to bring about right relations between the sixth and seventh
cervical vertebrae. Tension and irritation were removed. The
circumflex nerve ceased to manifest any undue irritation. The osteopath
almost invariably works from the center to periphery instead of the reverse.
Herpes Zoster. - An example of the osteopath's
use, or rather recognition of Hilton's law: A case of Herpes Zoster located
along the course of the left fifth intercostal nerve was given a grave
prognosis by a homeopathic physician. The patient visited an osteopath
immediately, hoping that some relief might be found for the intolerable
pain. The eruption extended from the spine to the median line in
front, forming a band about one inch wide. The fifth rib was found
rotated downward, thus lessening the fifth intercostal space and pressing
on the nerve at some point in its course. This rib was raised, even
though the osteopath's fingers rested directly upon the eruption, in order
to force the rib upward. The result was most gratifying. Pain
decreased almost immediately, and there was a rapid change in the appearance
of the eruption, the firey red giving place to a paler color. Those
papules which were just forming subsided, and those which had formed vesicles
began immediately to scab.
The patient could not stand erect, lifting the arm
caused increase of pain, likewise inspiration was lessened because it caused
pain. Hilton would say that these movements were curtailed to give
physiological rest. From the osteopathic standpoint, they are reflexes
which are not reparative in character, hence must be eliminated.
Every movement which tended to separate the fifth and sixth ribs caused
pain, hence the patient refrained from making them. The osteopath
separated these ribs, even though the process of doing so caused pain.
The structural defect causing the irritation was removed. In view
of the fact that Herpes Zoster is associated with posterior ganglionitis,
it may be that the subluxation of a rib is a secondary lesion and hence
only a secondary cause of pain. Clinical experience teaches us that
relief is obtained in these cases by separating the ribs which are approximated
by the muscular tension.
The Distribution of an Intercostal Nerve.
- The distribution of an intercostal nerve is to the pleura, intercostal
muscles and skin over these muscles, thus corresponding to the distribution
of nerve trunks to the synovial membrane of a joint, the muscles moving
the joint and the skin covering the joint.
Some of the Evil Results of Rest. - If we
give rest to all structures in which pain is located, we will help to fill
the world with stiff joints and serous adhesions, to say nothing of the
far reaching after affects of these structural defects upon the functional
activity of the nervous system. A differential diagnosis is required
in all cases of painful joints in order to determine whether it is wise
to disturb the physiologically protective reaction.
Hilton's law may be called an anatomical law; there
do not appear to be any exceptions to it, especially when supplemented
by his statement that "every fascia of the body has a muscle attached to
it, and every fascia throughout the body must be considered as the insertion
of a muscle." This carries the influence of motor nerves to points covered
by their sensory companions.
Head's Law. - Another law, or in this case
a comprehensive statement, has been made by Head in his writings in "Brain."
This is a statement of physiological transference of pain from its point
of origin to a point of conscious sensation. This physiological law
is stated as follows: "When a painful stimulus is applied to a part of
low sensibility in close central connection with a part of much higher
sensibility, the pain produced is felt in the part of higher sensibility
rather than in the part of lower sensibility to which the stimulus was
Application of the Law. - This physiological
law can be applied in two ways. First, we may consider the relative
sensibility of different portions of a nerve trunk. If a stimulus
is applied to a nerve trunk at some point in its course between its origin
and distribution, the pain caused by the stimulus will be felt, in the
area of distribution of the fibers of this nerve trunk rather than at the
point where the stimulus is applied. The skin, mucous or serous membrane
and muscle in which sensory nerves end are areas of high sensibility compared
with the trunk of the nerve. The brain is conscious of only the areas
of distribution of the sensory nerves, hence stimuli applied at the points
of low sensibility are referred to the areas of high sensibility.
Thus all lesions causing pressure upon nerve trunks cause pain, contraction,
or perversion of secretion in the areas of distribution. The patient
is not thoroughly conscious of any location but the area of distribution
which is an area of high sensibility.
The cases described under Hilton's law are applicable
here. In the case of inflamed shoulder joint the patient was not
conscious of the irritation at the spinal column the rotated vertebra -
this was an area of low sensibility in the course of the nerve trunk.
The brain attributed all the trouble to the terminations of the nerves
in the tissues of the joint. All of the reflexes acted accordingly.
The second application of this law is to the relative
intensity of areas of high sensibility. The areas in which sensory
nerves end are all areas of high sensibility, but some are higher than
others. We note in practice that sometimes a nerve trunk which supplies
several structures will manifest pain in a portion of its area of distribution
which is not the part in which the irritation is located. For example,
the sensory portion of the obturator nerve is distributed to the hip joint
and skin on the inner side of the knee. The skin seems to be an area
of higher sensibility than the interior of the hip joint, because in disease
of the hip joint the patient frequently complains of pain in the cutaneous
area rather than in the joint where the actual disease is located.
The Viscera. - The viscera are normally nonsensitive,
i. e., we are not conscious of possessing viscera, The pressure of food
in the stomach and the beat of the heart make no impression on our consciousness;
and so it is with all parts of the body governed by sympathetic nerves.
The viscera are areas of low sensibility, not low irritability, for they
are richly supplied with sensory nerves, upon the stimulation of which
active functioning depends. The response to stimuli of sensory nerves
in viscera is rapid, but normally this response takes place entirely outside
of our consciousness, the impression is not recognized as corning from
the viscera, but from a remote area of high sensibility in close central
connection with the less sensitive area. As an example, pain is felt
in the right shoulder, as a result of hyperaemia of the liver. The
pressure upon sensory nerves in the liver does not cause pain in the liver,
but refers it to a more sensitive area - the skin and muscles of the right
Chronic inflammation of the stomach may cause no
consciousness of pain in that organ, but may cause intense aching in the
Nerves of Conscious Sensation. - Cerebrospinal
nerves are nerves of consciousness, and seem to have the duty of registering
on the sensorium of our brains not only their own impressions, but the
impressions derived from that part of the sympathetic system in closest
central connection with them.
A close study of the segmental distribution of spinal nerves
and their connection with the sympathetic system by the rami-communicantes will
make Head's law of practical value in osteopathic diagnosis and therapeutics.